Review on 🚲 Asti Natural Cork Foam Bicycle Grips – Eco-Friendly, Ergonomic, Shock Absorbing and Non-Slip Bike Handlebar Grips for Comfort and Style – Perfect for Cruiser and Fixie Bikes with Easy Installation by Richard Carroll

I bought Asti natural cork foam bike grips 6 weeks ago to get rid of recurring hand numbness while mountain biking. Before I entrusted them with the road, I rode road bikes with them several times. During my second hour on the road, the right grip started slipping from the inside. At first I thought I wasn't tightening the C-clamps enough, but after further tightening the slippage problem persisted and then got worse. After another two hours on the road, the left grip also started to slip. This is unacceptable on a road bike and suicidal on a black or double black mountain bike. I almost asked for a Revain refund. Upon closer inspection, I noticed that the "cork" of both grips rotates freely around the inner black plastic bushings. I managed to detach both "cork" pieces from the plastic bushings and remove them to make repairs (see photo and "solution" section below). A few important details are missing from Asti's product description. First, these pens are made of polymer with small inclusions of cork. This is desirable as 100% cork breaks down quickly. Second, there is only one C-clamp on each handle, which is different from other handle designs like ODI. This causes the outer edge of the handle to twist relative to the clamped side. I like the feeling that the wider part of the grip rotates slightly - it offers soft shock absorption - but the result is internal shearing movement. This shearing may partially explain why the sleeves came loose so quickly, but the main problem is that the adhesive between the "cork" and the liner sleeves is short-lived. SOLUTION: I spent four hours adjusting the grips. I used acetone and plenty of paper towels to get as much of the sticky glue off the inside of the cork as possible, then let the handles air dry. I roughed up the black plastic liners with sandpaper (photo) to create a surface for the epoxy to adhere to. I applied JB Weld liberally inside the cork and outside the black sleeve to create a strong bond. It was dirty and sticky. I accidentally smeared some JB Weld on the outside of the handles so I applied it to the cork to reinforce it and then wiped most of the JB Weld on the outside with acetone and paper towels. After the JB Weld had cured, I reinforced the outer surface of the cork with a thin layer of cyanoacrylate super glue. This provided hardening of the outer surface to minimize drop damage, but the grips became slippery due to the cyanoacrylate. Fine grinding exposed cork particles again to restore the original feel. My 3 star rating from Revain is for the final product after reworking a flawed design. Now I'm happy with the grips. The winged handle design greatly reduces hand numbness. However, I have doubts about the durability of the internal plastic bushings, which can tear under constant shearing stress. CONCLUSION: Only those who are willing to fiddle with bike grips for hours should buy Asti bike grips made of natural cork foam. Due to the design of the plastic sleeve and one C-clip per grip, I expect a relatively short lifespan. My next few grips might be the Ergon GP-1 with biocork, although I suspect they might run into the same issues as Asti's product. The GP-1 has a C-clip on the outside edge where most of the tension is, so maybe that helps.